Measures of adiposity and future risk of ischemic stroke and coronary heart disease in older men and women

Adipokines and stroke: A systematic review and meta-analysis of disease risk and patient outcomes

Obesity is reported to increase stroke risk, with adipocyte-derived cytokines or adipokines implicated as mediators. However, the relationship between adipokines and stroke is not well clarified. Thus, we aimed to evaluate the association of adipokines with stroke using fully adjusted risk estimates that incorporated body mass index in a meta-analysis. Data from 52 studies (62,428 patients) were pooled in a random-effects meta-analysis. Adiponectin was independently associated with a lower risk of pre-existing stroke (adjusted odds ratio: 0.64 [95% confidence interval: 0.46-0.88], p < 0.01), whereas leptin (1.08 [1.00-1.17], p = 0.04), resistin (1.06 [1.04-1.08], p < 0.01) and visfatin (1.04 [1.01-1.07], p = 0.01) are associated with a higher risk of stroke, but none with incident stroke. Adipokines independently associated with an ischaemic stroke subtype were adiponectin (0.48 [0.30-0.77], p < 0.01), leptin (1.10 [1.01-1.20], p = 0.04), and resistin (1.06 [1.04-1.08], p < 0.01). Fatty acid-binding protein-4 (FABP-4) independently predicted 6-month poor functional outcomes in stroke patients (adjusted hazard ratio: 1.09 [1.06-1.12], p < 0.01); whereas both FABP-4 (1.17 [1.03-1.34], p = 0.01) and visfatin (1.24 [1.00-1.55], p = 0.05) were predictive of 6-month mortality. Adipokines are associated with a greater risk of pre-existing stroke, but not with the relationship with incident stroke. Adipokines, such as FABP-4 and visfatin, may serve as biomarkers of stroke severity and worsening of stroke outcomes.

Epicardial fat and incident heart failure with preserved ejection fraction in patients with coronary artery disease

BACKGROUND

We aimed to determine, whether epicardial adipose tissue (EAT) as local source of inflammation, as well as its change over time, associates with the development of heart failure with preserved ejection fraction (HFpEF) in patients with coronary artery disease.

METHODS AND RESULTS

We retrospectively included 379patients (aged 65.2 ± 11.7 years, 70.2%male) with coronary artery disease but without heart failure at baseline, undergoing clinical and echocardiographic assessment in 2010-2013 and receiving a second assessment in 2014-2018. EAT thickness was defined as space between the myocardium and the pericardium and indexed (EATi) by body surface area. Change in EATi was calculated as the difference of follow-up and baseline EATi. HFpEF was defined according to presence of dyspnea, elevated natriuretic peptides, and structural and/or functional alterations on echocardiography in accordance with current European Society of Cardiology guidelines. During a median follow-up of 4.3 years, 142patients (37.5%) developed HFpEF. Patients with onset of HFpEF had higher EATi at baseline (2.4 ± 1.3 vs. 1.9 ± 0.9 mm/m², p = 0.001). In multivariable regression analysis, EATi associated with onset of HFpEF (1.25 [1.01-1.54], p = 0.04). Likewise, an increase in EATi over time was linked HFpEF development, independent of other risk factors and baseline EATi (1.39 [1.04-1.87], p = 0.03). EATi was significantly associated with follow-up b-type natriuretic peptide (BNP) levels (4.31[0.58-8.05], p = 0.024), but not with baseline BNP (2.24[-0.27-4.76], p = 0.08).

CONCLUSION

EATi is associated with the development of HFpEF. The finding of changes in EATi altering the risk of HFpEF manifestation support the rationale for further research on epicardial fat modulation as a treatment target for HFpEF.

Associations of Skeletal Muscle Mass and Fat Mass With Incident Cardiovascular Disease and All-Cause Mortality: A Prospective Cohort Study of UK Biobank Participants

Background There is debate whether body mass index is a good predictor of health outcomes because different tissues, namely skeletal muscle mass (SMM) and fat mass (FM), may be differentially associated with risk. We investigated the association of appendicular SMM (aSMM) and FM with fatal and nonfatal cardiovascular disease (CVD) and all-cause mortality. We compared their prognostic value to that of body mass index. Methods and Results We studied 356 590 UK Biobank participants aged 40 to 69 years with bioimpedance analysis data for whole-body FM and predicted limb muscle mass (to calculate aSMM). Associations between aSMM and FM with CVD and all-cause mortality were examined using multivariable Cox proportional hazards models. Over 3 749 501 person-years of follow-up, there were 27 784 CVD events and 15 844 all-cause deaths. In men, aSMM was positively associated with CVD incidence (hazard ratio [HR] per 1 SD 1.07; 95% CI, 1.06-1.09) and there was a curvilinear association in women. There were stronger positive associations between FM and CVD with HRs per SD of 1.20 (95% CI, 1.19-1.22) and 1.25 (95% CI, 1.23-1.27) in men and women respectively. Within FM tertiles, the associations between aSMM and CVD risk largely persisted. There were J-shaped associations between aSMM and FM with all-cause mortality in both sexes. Body mass index was modestly better at discriminating CVD risk. Conclusions FM showed a strong positive association with CVD risk. The relationship of aSMM with CVD risk differed between sexes, and potential mechanisms need further investigation. Body fat and SMM bioimpedance measurements were not superior to body mass index in predicting population-level CVD incidence or all-cause mortality.

Abdominal obesity and risk of CVD: a dose-response meta-analysis of thirty-one prospective studies

This meta-analysis aimed to study the relationship between abdominal obesity and the risk of CVD by waist circumference (WC), waist:hip ratio (WHR) and waist:height ratio (WHtR). We systematically searched PubMed, Embase and Web of Science. Prospective studies that estimated cardiovascular events by WC, WHR and WHtR were included in this study. Pooled relative risks with 95 % CI were calculated using random effects models. A total of thirty-one studies were included in the meta-analysis, including 669 560 participants and 25 214 cases. Compared the highest with the lowest category of WC, WHR and WHtR, the summary risk ratios were 1·43 (95 % CI, 1·30, 1·56, P < 0·001), 1·43 (95 % CI, 1·33, 1·54, P < 0·001) and 1·57 (95 % CI, 1·37, 1·79, P < 0·001), respectively. The linear dose-response analysis revealed that the risk of CVD increased by 3·4 % for each 10 cm increase of WC, and by 3·5 and 6·0 % for each 0·1 unit increase of WHR and WHtR in women, respectively. In men, the risk of CVD increased by 4·0 % for each 10 cm increase of WC, and by 4·0 and 8·6 % for each 0·1 unit increase of WHR and WHtR, respectively. Collectively, abdominal obesity is associated with an increased risk of CVD. WC, WHR and WHtR are good indicators for the prediction of CVD.

Effect of Post-Stroke Rehabilitation on Body Mass Composition in Relation to Socio-Demographic and Clinical Factors

Background and objectives: Stroke is one of the leading causes of morbidity, mortality and long-term adult disability. The aim of this study was to assess the changes in body mass composition in patients after stroke in connection with selected socio-demographic and clinical factors (sex, age, type of stroke and time from the first symptoms) following the rehabilitation process. Materials and Methods: The study group consisted of 100 post-stroke subjects who participated in a comprehensive rehabilitation program for a duration of five weeks. The measurements of body composition by a Tanita MC 780 MA analyser were performed on the day of admission to hospital, on the day of discharge (after 5 weeks) and 12 weeks after discharge from hospital. Results: It was shown that before rehabilitation (Exam I) in the study group there were significant differences in body composition relative to sex, age and time from stroke. The rates of fat mass % and visceral fat level decreased after rehabilitation (Exam II) in both males and females. Exam II, at the end hospital rehabilitation, showed lower levels of fat mass %, visceral fat level, as well as fat-free mass % and higher values of total body water % and muscle mass %. In Exam III, i.e., 12 weeks after discharge, all of the parameters retained their values. Conclusions: The study shows an association between stroke risk factors (primarily age, sex and time from the onset of the first symptoms of stroke) and body mass composition resulting from rehabilitation. The type of stroke and the effects of rehabilitation on body mass components showed no differences. Comprehensive rehabilitation had a positive effect on the body mass components.

Adiposity Indicators as Cardio-Metabolic Risk Predictors in Adults from Country with High Burden of Obesity

BACKGROUND

In Qatar more than 70% 0f the adults are overweight and obese. Different adiposity assessment methods have been proposed to identify individuals at cardio-metabolic risk.

PURPOSE

This study aimed to compare anthropometric indicators with Dual-energy X-ray absorptiometry (DXA) -derived adiposity indicators in predicting cardio-metabolic risk among Qatari adults.

PATIENTS AND METHODS

A random sample of five hundred and fifty-eight (558) healthy Qatari adults (men and women) aged 20 to 50 years was obtained from Qatar Biobank survey data. Anthropometric data (weight, height, and waist circumference), the DXA-derived data, and cardio-metabolic (CM) risk parameters were analyzed. A Spearman partial correlation coefficient, Receiver Operating Characteristics (ROC) curve and an area under curve (AUC) were used to assess the predicting ability of adiposity indicators for CM risk factors.

RESULTS

Adiposity indices (anthropometric and DXA) were significantly correlated with most of the CM indicators (r= -0.292 to 0.486, p< 0.001). The AUC of waist to height ratio (WHtR) was significantly higher than that of body mass index (BMI) and waist circumference (WC) in the prediction of low high density lipoprotein (HDL) (AUC=0.65, AUC=0.59; AUC=0.64), high low density lipoprotein (LDL) (AUC=0.67; AUC=0.62; AUC=0.66), high cholesterol (AUC=0.66; AUC=0.63; AUC=0.63), and high Homeostatic Model Assessment- (HOMA) (AUC= 0.81; AUC= 0.78; AUC=0.78). Among DXA- parameters, trunk fat had the highest AUCs for total cholesterol (AUC= 0.64, CI=0.56, 0.73), triglycerides and glucose index (TyG) (AUC=0.69, CI=0.64, 0.74), and HOMA (AUC=0.78, CI= 0.73, 0.84).

CONCLUSION

Results of the present study show that adiposity indicators (WC and WHtR) are clinically valuable tools to identify individuals at risk of CVD compared to DXA-derived parameters, while DXA can provide more accurate estimates.

Body adiposity indicators and cardiometabolic risk: Cross-sectional analysis in participants from the PREDIMED-Plus trial

BACKGROUND & AIMS

Excess adiposity is associated with poor cardiometabolic (CM) health. To date, several techniques and indicators have been developed to determine adiposity. We aimed to compare the ability of traditional anthropometric, as well as standard and novel DXA-derived parameters related to overall and regional adiposity, to evaluate CM risk.

METHODS

Using the cross-sectional design in the context of the PREDIMED-Plus trial, 1207 Caucasian senior men and women with overweight/obesity and metabolic syndrome (MetS) were assessed. At baseline, anthropometry- and DXA-measured parameters of central, visceral, peripheral and central-to-peripheral adiposity together with comprehensive set of CM risk factors were obtained. Partial correlations and areas under the ROC curve (AUC) were estimated to compare each adiposity measure with CM risk parameters, separately for men and women, and in the overall sample.

RESULTS

DXA-derived indicators, other than percentage of total body fat, showed stronger correlations (rho -0.172 to 0.206, p < 0.001) with CM risk than anthropometric indicators, after controlling for age, diabetes and medication use. In both sexes, DXA-derived visceral adipose tissue measures (VAT, VAT/Total fat, visceral-to-subcutaneous fat) together with lipodystrophy indicators (Trunk/Legs fat and Android/Gynoid fat) were strongly and positively correlated (p < 0.001) with glycated hemoglobin (HbA1c), the triglyceride and glucose index (TyG), triglycerides (TG), the ratio TG/HDL-cholesterol (TG/HDL-C), and were inversely related to HDL-C levels (p < 0.001). Furthermore, in AUC analyses for both sexes, VAT/Total fat showed the highest predictive ability for abnormal HbA1c levels (AUC = 0.629), VAT for TyG (AUC = 0.626), both lipodystrophy indicators for TG (AUCs = 0.556), and Trunk/Legs fat for HDL-C (AUC = 0.556) and TG/HDL-C (AUC = 0.581).

CONCLUSIONS

DXA regional adiposity measures offer advantages beyond traditional anthropometric and DXA overall adiposity indicators for CM risk assessment in senior overweight/obese subjects with MetS. In particular, in both sexes, visceral adiposity better stratifies individuals at risk for glucose abnormalities, and indicators of lipodystrophy better predict markers of dyslipidemia.

The role of obesity in carotid plaque instability: interaction with age, gender, and cardiovascular risk factors

BACKGROUND

In the last decade, several studies have reported an unexpected and seemingly paradoxical inverse correlation between BMI and incidence of cardiovascular diseases. This so called "obesity paradox effect" has been mainly investigated through imaging methods instead of histologic evaluation, which is still the best method to study the instability of carotid plaque. Therefore, the purpose of our study was to evaluate by histology the role of obesity in destabilization of carotid plaques and the interaction with age, gender and other major cerebrovascular risk factors.

METHODS

A total of 390 carotid plaques from symptomatic and asymptomatic patients submitted to endarterectomy, for whom complete clinical and laboratory assessment of major cardiovascular risk factors was available, were studied by histology. Patients with a BMI ≥ 30.0 kg/m2 were considered as obese. Data were analyzed by multivariate logistic regression and for each variable in the equation the estimated odds ratio (OR) was calculated.

RESULTS

Unstable carotid plaque OR for obese patients with age < 70 years was 5.91 (95% CI 1.17-29.80), thus being the highest OR compared to that of other risk factors. Unstable carotid plaque OR decreased to 4.61 (95% CI 0.54-39.19) in males ≥ 70 years, being only 0.93 (95% CI 0.25-3.52) among women. When obesity featured among metabolic syndrome risk factors, the OR for plaque destabilization was 3.97 (95% CI 1.81-6.22), a significantly higher value compared to OR in non-obese individuals with metabolic syndrome (OR = 1.48; 95% CI 0.86-2.31). Similar results were obtained when assessing the occurrence of acute cerebrovascular symptoms.

CONCLUSIONS

Results from our study appear to do not confirm any paradoxical effect of obesity on the carotid artery district. Conversely, obesity is confirmed to be an independent risk factor for carotid plaque destabilization, particularly in males aged < 70 years, significantly increasing such risk among patients with metabolic syndrome.

Body fat distribution and risk of incident ischemic stroke in men and women aged 50 to 74 years from the general population. The KORA Augsburg cohort study

Background

It remains controversial whether measures of general or abdominal adiposity are better risk predictors for ischemic stroke. Furthermore, so far it is unclear whether body fat mass index (BFMI) and fat free mass index (FFMI) are risk predictors for ischemic stroke. This study examined the sex-specific relevance of body mass index (BMI), BROCA Index, waist circumference (WC), waist-height ratio (WHtR), BFMI and FFMI for the development of ischemic stroke in a Caucasian population.

Material and methods

The prospective population-based cohort study was based on 1917 men and 1832 women (aged 50 to 74 years) who participated in the third (1994/95) or fourth (1999/2001) MONICA/KORA Augsburg survey. Subjects were free of stroke at baseline. Standardized anthropometric and bioelectric impedance measurements were obtained at baseline. Hazard ratios (HR) were estimated from Cox proportional hazard models.

Results

During a median follow-up of 9.3 years 128 ischemic strokes occurred in men and 81 in women, respectively. Coded as quartiles WC and WHtR were significantly associated with incident stroke in multivariable analyses in women (comparing the 4^th vs. the bottom quartile), but none of the adiposity measures was significantly associated with incident stroke in multivariable adjusted analyses in men. When anthropometric measures were used as continuous variables, these findings were confirmed. After multivariable adjustment the associations between obesity measures and incident ischemic stroke were statistically significant only for WC (HR 1.39, 95%CI 1.12-1.72) and WHtR in women (HR 1.39, 95%CI 1.12-1.73) per increase of 1 standard deviation. In both sexes the measures BFMI and FFMI were no independent predictors for incident ischemic stroke.

Conclusions

Abdominal obesity measures are independent predictors of incident ischemic stroke in women but not in men from the general adult population. Thus, it may be of particular importance for women to prevent central obesity in order to reduce their risk of ischemic stroke.

Adipokines in neurovascular diseases

Adipose tissue is now described as an endocrine organ secreting a number of adipokines contributing to the development of inflammation and metabolic imbalance, but also endothelial dysfunction, vascular remodeling, atherosclerosis, and ischemic stroke. Leptin, adiponectin, and resistin are the most studied adipokines which play important roles in the regulation of cardiovascular homeostasis. Leptin and adiponectin mediate both proatherogenic and antiatherogenic responses. Leptin and adiponectin have been linked to the development of coronary heart disease and may be involved in the underlying biological mechanism of ischemic stroke. Resistin, a pro-inflammatory cytokine, is predictive of atherosclerosis and poor clinical outcomes in patients with coronary artery disease and ischemic stroke. The changes in serum levels of novel adipokines apelin, visfatin are also associated with acute ischemic stroke. These adipokines have been proposed as potential prognostic biomarkers of cardiovascular mortality/morbidity and therapeutic targets in patients with cardiometabolic diseases. In this article, we summarize the biologic role of the adipokines and discuss the link between dysfunctional adipose tissue and metabolic/inflammation imbalance, consequently endothelial damage, progression of atherosclerotic disease, and the occurrence of ischemic stroke.

Decreasing incidence of coronary heart disease in extreme obesity (BMI≥40)-A single centre experience

AIM

The aim of our comprehensive single centre analysis was to evaluate the incidence of coronary heart disease (CHD) in extremely obese patients.

METHODS AND RESULTS

Between 2005 and 2015 we investigated retrospectively 23,359 patients undergoing cardiac catheterisation in our institution. Patients were divided in six weight classes according to World Health Organization (WHO) criteria [1] (WHO, 2000). Cardiovascular risk factors, comorbidities, CCS stadium [2] (Cox and Naylor, 1992) and NYHA functional class [3] (The Criteria Committee of the New York Heart Association, 1994) were retrieved from electronic patient records. Using multivariable analysis the odds ratio for the target variable CHD with presence of >50% angiographic stenosis was ≥1 with regard to age (OR 1.049, 95% CI 1.045-1.052), male sex (OR 2.507, 95% CI 2.329-2.699), cardiovascular risk factors, atherosclerosis (OR 1.651, 95% CI 1.498-1.820), and presence of angina (OR 4.408, 95% CI 3.892-4.993). NYHA functional class I-IV, absence of angina (OR 0.818, 95% CI 0.729-0.918), and BMI≥40 (OR 0.592, 95% CI 0.494-0.709) resulted in an odds ratio of ≤1. Underweight patients had a higher (5.3%) and overweight (1.2%) and obese patients (class I 0.9% and II 1.1%) a slightly lower all-cause in-hospital mortality compared to extremely obese patients (1.6%).

CONCLUSION

Severely obese patients treated in our hospital surprisingly showed a decreased incidence of CHD (46.1% in normal weight and 38.6% in extremely obese patients) while comorbidities increased CHD as expected. Although CHD burden was lower, obesity and associated comorbidities resulted in higher all-cause-in-hospital mortality.

Relation of Adiponectin to All-Cause Mortality, Cardiovascular Mortality, and Major Adverse Cardiovascular Events (from the Dallas Heart Study)

Adiponectin is a key component in multiple metabolic pathways. Studies evaluating associations of adiponectin with clinical outcomes in older adults have reported conflicting results. We investigated the association of adiponectin with mortality and cardiovascular disease (CVD) morbidity in a young, multiethnic adult population. We analyzed data from participants in the Dallas Heart Study without baseline CVD who underwent assessment of total adiponectin from 2000 to 2002. The primary outcome of all-cause mortality was assessed over median 10.4 years of follow-up using multivariable-adjusted Cox proportional hazards models. Secondary outcomes included CVD mortality, major adverse cardiovascular and cerebrovascular events (MACCE), and heart failure (HF). The study cohort included 3,263 participants, mean age 43.4 years, 44% women, and 50% black. There were 184 deaths (63 CVD), 207 MACCE, and 46 HF events. In multivariable models adjusted for age, gender, race, hypertension, diabetes, smoking, high-density lipoprotein cholesterol-C, hyperlipidemia, high-sensitivity C-reactive protein level, estimated glomerular filtration rate, and body mass index, increasing adiponectin quartiles were positively associated with all-cause mortality Q4 versus Q1 (hazard ratio [HR] = 2.27; 95% confidence interval [CI] 1.47, 3.50); CVD mortality Q4 versus Q1 (HR = 2.43; 95% CI 1.15, 5.15); MACCE Q4 versus Q1 (HR = 1.71; 95% CI 1.13, 2.60); and HF Q4 versus Q1 (HR = 2.95; 95% CI 1.14, 7.67). Findings were similar with adiponectin as a continuous variable and consistent across subgroups defined by age, gender, race, obesity, diabetes, metabolic syndrome, or elevated high-sensitivity C-reactive protein. In conclusion, higher adiponectin was associated with increased mortality and CVD morbidity in a young, multiethnic population. These findings may have implications for strategies aimed at lowering adiponectin to prevent adverse outcomes.

[Stroke - lifestyle and environment]

Lifestyle modifications and environmental factors are important for stroke prevention and rehabilitation after stroke. The individual stroke risk may be modified by factors like physical activity, body weight and nutrition, special dietary supplements such as vitamins, smoking, consumption of tea, coffee and alcohol, psychological factors and by keeping a pet. The focus of this article lies on measures for stroke prevention. For certain topics, it also comments on factors that are important during rehabilitation after stroke.

An association study between epicardial fat thickness and cognitive impairment in the elderly

The amount of fat surrounding the heart, called epicardial adipose tissue (EAT), is a marker of cardiometabolic risk and correlates with the quantity of visceral adipose tissue (VAT). The amount of VAT is associated with an increased risk of cardiovascular and cerebrovascular disease and with cognitive impairment. We aimed to evaluate the association between EAT thickness as a measure of VAT and cognitive function. In 71 elderly subjects (mean age 72.7 ± 7.1 yr) we measured EAT thickness through transthoracic echocardiography, assessed the metabolic profile through evaluation of biochemical parameters, and estimated the cognitive function via the Mini Mental State Examination (MMSE). We found that greater EAT thickness was associated with lower cognitive performance evaluated by MMSE (P < 0.01) independently of the presence or absence of metabolic syndrome or obesity. Lower MMSE results were also associated with the presence of metabolic syndrome (P < 0.01), elevated HOMA index (P < 0.01), and high BMI values (P < 0.01). The results of mediation analysis confirmed that the total effect of metabolic syndrome, HOMA, and BMI on MMSE is mainly explained by an indirect effect through EAT thickness. In conclusion, increased EAT thickness assessed by transthoracic echocardiography is associated with deficient results of psychometric tests assessing cognitive performance and may consistently foresee impairment of cognition in the elderly.

Insulin-independent role of adiponectin receptor signaling in Drosophila germline stem cell maintenance

Adipocytes have key endocrine roles, mediated in large part by secreted protein hormones termed adipokines. The adipokine adiponectin is well known for its role in sensitizing peripheral tissues to insulin, and several lines of evidence suggest that adiponectin might also modulate stem cells/precursors. It remains unclear, however, how adiponectin signaling controls stem cells and whether this role is secondary to its insulin-sensitizing effects or distinct. Drosophila adipocytes also function as an endocrine organ and, although no obvious adiponectin homolog has been identified, Drosophila AdipoR encodes a well-conserved homolog of mammalian adiponectin receptors. Here, we generate a null AdipoR allele and use clonal analysis to demonstrate an intrinsic requirement for AdipoR in germline stem cell (GSC) maintenance in the Drosophila ovary. AdipoR null GSCs are not fully responsive to bone morphogenetic protein ligands from the niche and have a slight reduction in E-cadherin levels at the GSC-niche junction. Conversely, germline-specific overexpression of AdipoR inhibits natural GSC loss, suggesting that reduction in adiponectin signaling might contribute to the normal decline in GSC numbers observed over time in wild-type females. Surprisingly, AdipoR is not required for insulin sensitization of the germline, leading us to speculate that insulin sensitization is a more recently acquired function than stem cell regulation in the evolutionary history of adiponectin signaling. Our findings establish Drosophila female GSCs as a new system for future studies addressing the molecular mechanisms whereby adiponectin receptor signaling modulates stem cell fate.

The Intricate Network of Adipokines and Stroke

Cerebrovascular disorders, particularly ischemic stroke, are one of the most common neurological disorders. High rates of overweight and obesity support an interest in the role of adipose tissue and adipose tissue releasing cytokines in inducing associated comorbidities. Adipokines can serve as a key messenger to central energy homeostasis and metabolic homeostasis. They can contribute to the crosstalk between adipose tissue and brain. However recent research has offered ambiguous data on the network of adipose tissue, adipokines, and vascular disorders. In our paper we provide a critical insight into the role of adipokines in evolution of ischemic stroke.

Guidelines for the primary prevention of stroke: a statement for healthcare professionals from the American Heart Association/American Stroke Association

The aim of this updated statement is to provide comprehensive and timely evidence-based recommendations on the prevention of stroke among individuals who have not previously experienced a stroke or transient ischemic attack. Evidence-based recommendations are included for the control of risk factors, interventional approaches to atherosclerotic disease of the cervicocephalic circulation, and antithrombotic treatments for preventing thrombotic and thromboembolic stroke. Further recommendations are provided for genetic and pharmacogenetic testing and for the prevention of stroke in a variety of other specific circumstances, including sickle cell disease and patent foramen ovale.

Obesity related risk of sudden cardiac death in the atherosclerosis risk in communities study

OBJECTIVE

To examine the association of body mass index (BMI), waist circumference (WC) and waist hip ratio (WHR) with sudden cardiac death (SCD) in community dwelling individuals.

METHODS

Data from a multicentre, prospective, cohort study of 14 941 men and women (African American, and white), aged 45-64 years, participating in the Atherosclerosis Risk in Communities study was analysed. Obesity measures were assessed at baseline (1987-1989). SCD was adjudicated by a committee.

RESULTS

At enrolment mean±SD age of the participants was 54±6 years (55% female; 26% African American). During 12.6±2.5 years of follow-up, 253 SCD occurred (incidence rate 1.34/100 person-years). The association between obesity and SCD differed by smoking status (interaction p≤0.01). In models adjusting for age, sex, race, study centre and education level, SCD risk was positively associated (p<0.001) with BMI, WC and WHR in non-smokers, but not in smokers. WHR was more strongly associated with SCD in non-smokers than was BMI or WC (HR per SD increment (95% CI) 2.00 (1.65 to 2.42); 1.34 (1.15 to 1.56) and 1.49 (1.28 to 1.74), respectively). After adjustment for potential mediators (hypertension, diabetes, lipid profile, prevalent coronary heart disease, heart failure, and LV hypertrophy), non-smokers in the highest WHR category (>0.95 in women; >1.01 in men) had double the risk of SCD (HR 2.03, 95% CI 1.19 to 3.46; incidence rate 1.43/1000 person-years) versus those with normal WHR.

CONCLUSIONS

General obesity is associated with increased risk of SCD in middle-aged, non-smoking individuals, mediated by traditional cardiovascular risk factors. Central obesity, however, is independently associated with SCD by pathways that remain to be elucidated.

Advanced glycation/glycoxidation endproduct carboxymethyl-lysine and incidence of coronary heart disease and stroke in older adults

BACKGROUND

Advanced glycation/glycoxidation endproducts (AGEs) accumulate in settings of increased oxidative stress--such as diabetes, chronic kidney disease and aging--where they promote vascular stiffness and atherogenesis, but the prospective association between AGEs and cardiovascular events in elders has not been previously examined.

METHODS

To test the hypothesis that circulating levels of N(ɛ)-carboxymethyl-lysine (CML), a major AGE, increase the risk of incident coronary heart disease and stroke in older adults, we measured serum CML by immunoassay in 2111 individuals free of prevalent cardiovascular disease participating in a population-based study of U.S. adults ages 65 and older.

RESULTS

During median follow-up of 9.1 years, 625 cardiovascular events occurred. CML was positively associated with incident cardiovascular events after adjustment for age, sex, race, systolic blood pressure, anti-hypertensive treatment, diabetes, smoking status, triglycerides, albumin, and self-reported health status (hazard ratio [HR] per SD [0.99 pmol/l] increase=1.11, 95% confidence interval [CI]=1.03-1.19). This association was not materially attenuated by additional adjustment for C-reactive protein, estimated glomerular filtration rate (eGFR), and urine albumin/creatinine ratio. Findings were similar for the component endpoints of coronary heart disease and stroke.

CONCLUSIONS

In this large older cohort, CML was associated with an increased risk of cardiovascular events independent of a wide array of potential confounders and mediators. Although the moderate association limits CML's value for risk prediction, these community-based findings provide support for clinical trials to test AGE-lowering therapies for cardiovascular prevention in this population.

Ambulatory blood pressure monitoring for risk stratification in obese and non-obese subjects from 10 populations

Overweight clusters with high blood pressure (BP), but the independent contribution of both risk factors remains insufficiently documented. In a prospective population study involving 8467 participants (mean age 54.6 years; 47.0% women) randomly recruited from 10 populations, we studied the contribution of body mass index (BMI) to risk over and beyond BP, taking advantage of the superiority of ambulatory over conventional BP. Over 10.6 years (median), 1271 participants (15.0%) died and 1092 (12.9%), 637 (7.5%) and 443 (5.2%) experienced a fatal or nonfatal cardiovascular, cardiac or cerebrovascular event. Adjusted for sex and age, low BMI (<20.7 kg m(-2)) predicted death (hazard ratio (HR) vs average risk, 1.52; P<0.0001) and high BMI (> or = 30.9 kg m(-2)) predicted the cardiovascular end point (HR, 1.27; P=0.006). With adjustments including 24-h systolic BP, these HRs were 1.50 (P<0.001) and 0.98 (P=0.91), respectively. Across quartiles of the BMI distribution, 24-h and nighttime systolic BP predicted every end point (1.13 < or = standardized HR < or = 1.67; 0.046 < or = P<0.0001). The interaction between systolic BP and BMI was nonsignificant (P > or = .22). Excluding smokers removed the contribution of BMI categories to the prediction of mortality. In conclusion, BMI only adds to BP in risk stratification for mortality but not for cardiovascular outcomes. Smoking probably explains the association between increased mortality and low BMI.

Relations of plasma total and high-molecular-weight adiponectin to new-onset heart failure in adults ≥65 years of age (from the Cardiovascular Health study)

Adiponectin exhibits cardioprotective properties in experimental studies, but elevated levels have been linked to increased mortality in older adults and patients with chronic heart failure (HF). The adipokine's association with new-onset HF remains less well defined. The aim of this study was to investigate the associations of total and high-molecular weight (HMW) adiponectin with incident HF (n = 780) and, in a subset, echocardiographic parameters in a community-based cohort of adults aged ≥65 years. Total and HMW adiponectin were measured in 3,228 subjects without prevalent HF, atrial fibrillation or CVD. The relations of total and HMW adiponectin with HF were nonlinear, with significant associations observed only for concentrations greater than the median (12.4 and 6.2 mg/L, respectively). After adjustment for potential confounders, the hazard ratios per SD increment in total adiponectin were 0.93 (95% confidence interval 0.72 to 1.21) for concentrations less than the median and 1.25 (95% confidence interval 1.14 to 1.38) higher than the median. There was a suggestion of effect modification by body mass index, whereby the association appeared strongest in participants with lower body mass indexes. Consistent with the HF findings, higher adiponectin tended to be associated with left ventricular systolic dysfunction and left atrial enlargement. Results were similar for HMW adiponectin. In conclusion, total and HMW adiponectin showed comparable relations with incident HF in this older cohort, with a threshold effect of increasing risk occurring at their median concentrations. High levels of adiponectin may mark or mediate age-related processes that lead to HF in older adults.

Association of obesity with cardiovascular disease mortality in the PLCO trial

OBJECTIVE

Obesity is a risk factor for cardiovascular disease (CVD) mortality, but the association between obesity and specific causes of CVD mortality is still under investigation.

METHOD

We prospectively examined body-mass index (BMI) in relation to CVD-specific causes of death in approximately 86,000 US men and women in the Prostate, Lung, Colorectal and Ovarian (PLCO) Cancer Screening Trial, followed for up to 13 years. BMI was calculated from self-reported weight and height at baseline. Hazard ratios (HRs) were calculated overall and stratified by sex, smoking status, and educational level.

RESULT

Overweight non-obese participants (BMI: 25.0-29.9) were not at excess risk for CVD mortality (HR and CIs are 1.02 [0.92-1.13]), compared to participants of normal BMI (18.5-24.9). Excess CVD mortality was observed for participants of BMI 30.0-34.9 (HR and CIs: 1.29 [1.13-1.48]), BMI 35.0-39.9 (HR and CIs: 1.87 [1.51-2.32]) and BMI 40.0+ (HR and CIs: 2.21 [1.57-3.21]) (p<0.001 for trend). BMI was unrelated to mortality due to stroke. The observed association of BMI with CVD was independent of gender, smoking status and educational level.

CONCLUSION

Obesity is associated with increased mortality due to CVD.

Effect of basal metabolic rate on the bone mineral density in middle to old age women in Taiwan

BACKGROUND

Basal metabolic rate (BMR) reflects a combination of cardiopulmonary function and lean body mass resulting from regular physical activity. Though many studies have examined the relationships between bone mineral density (BMD) and body composition, little is known regarding the relationship between BMD and BMR.

OBJECTIVE

The purpose of this study was to investigate the relationship between BMR, anthropometric parameters, body composition and BMD in postmenopausal women in Taiwan.

METHODS

Two hundred and eighty-nine women between the ages of 40 and 80 years were included in this cross-sectional study. The following parameters were assessed: height, body weight, total body fat (TBF), BMR, waist-to-hip ratio, grip strength, and back strength. Differences in all variables between osteoporotic and non-osteoporotic women (categorized according to decades in age) were calculated using a one-way analysis of variance (ANOVA) and a Bonferroni post-hoc test. Multiple linear regression with a backward stepwise approach was performed to evaluate the relationship between these measurements and BMD.

RESULTS

Among women over 50 years of age, those who were non-osteoporotic had higher BMR, BMI, and body fat by comparison to their osteoporotic counterparts (p<0.05 for all). Multiple linear regression revealed that BMR and body fat significantly predicted BMD of the femoral neck (adjusted beta coefficients of 0.304 and 0.190, respectively; p<0.05 for both). BMR and body fat also predicted an increased vertebral BMD (adjusted beta coefficients of 0.310 and 0.141, respectively; p<0.05 for both).

CONCLUSION

BMR is closely associated with BMD in elderly persons, and may be a novel target for interventions aimed at preventing the age-related decline in BMD.

Should visceral fat, strictly linked to hepatic steatosis, be depleted to improve survival?

Numerous epidemiologic studies have implicated abdominal obesity as a major risk factor for insulin resistance, type 2 diabetes mellitus, cardiovascular disease, stroke, metabolic syndrome and its further expression, i.e., nonalcoholic fatty liver disease and death. Using novel models of visceral obesity, several studies have demonstrated that the relationship between visceral fat and longevity is causal, while the accrual of subcutaneous fat does not appear to play an important role in the etiology of disease risk. The need of reducing the visceral fat to improve survival, mainly taking into account the strict link between nonalcoholic fatty liver disease and the coronary artery disease is discussed.

Total and high-molecular-weight adiponectin and risk of coronary heart disease and ischemic stroke in older adults

CONTEXT

Adiponectin is atheroprotective in the laboratory, but prospective studies have shown opposite associations with cardiovascular disease (CVD) in healthy middle-aged populations (protective) and older cohorts (adverse). Whether this relates to different proportions of high-molecular-weight (HMW) adiponectin is unknown.

OBJECTIVE

The aim of the study was to test the hypothesis that total adiponectin is directly associated, but HMW adiponectin is inversely related, with CVD in older adults.

DESIGN, SETTING, AND PARTICIPANTS

We evaluated 3290 participants free of prevalent CVD in a longitudinal cohort study of U.S. adults aged 65 yr and older.

MAIN OUTCOME MEASURES

We measured incident CVD (n = 1291), comprising coronary heart disease and ischemic stroke.

RESULTS

Total and HMW adiponectin were tightly correlated (r = 0.94). Cubic splines adjusted for potential confounders revealed that the associations of total and HMW adiponectin with CVD were U-shaped, with inflection points of 20 and 10 mg/liter, respectively. After controlling for potential confounding, levels of total and HMW adiponectin below these cutpoints tended to be inversely associated with incident CVD, driven by their significant or near-significant relations with coronary heart disease [hazard ratio (HR), 0.85 per sd increase; 95% confidence interval (CI), 0.75-96; and HR, 0.87; 95% CI, 0.75-1.01, respectively]. These associations were abrogated by additional inclusion of putative metabolic intermediates. Above these cutpoints, however, both total and HMW adiponectin were significantly directly associated with CVD after adjustment for confounders and, particularly, mediators (HR, 1.20 per sd increase; 95% CI, 1.06-1.35; and HR, 1.12; 95% CI, 1.02-1.24, respectively).

CONCLUSION

In community-living elders, total and HMW adiponectin showed similar U-shaped relationships with CVD. The inverse relation in the lower range, but not the direct association at the higher end, disappeared after inclusion of putative intermediates, suggesting that high levels may reflect adverse processes separate from adiponectin's beneficial glycometabolic properties.

Associations of total and high-molecular-weight adiponectin with all-cause and cardiovascular mortality in older persons: the Cardiovascular Health Study

BACKGROUND

Adiponectin shows opposite associations with adverse outcomes in healthy middle-aged populations (lower risk) and cohorts with prevalent cardiovascular disease, heart failure, or advanced age (higher risk).

METHODS AND RESULTS

In a population-based study of older adults, we examined the relationships of total and high-molecular-weight adiponectin with mortality among subgroups defined by baseline cardiovascular status: No cardiovascular disease, heart failure, or atrial fibrillation (group 1); cardiovascular disease but no heart failure/atrial fibrillation (group 2); and heart failure/atrial fibrillation (group 3). We found significant differences in the associations with all-cause mortality across the groups. The association in group 1 was U-shaped; increasing levels of total adiponectin up to 12.4 mg/L were associated with lower mortality after adjustment for confounders (hazard ratio=0.81 per 1 SD [95% confidence interval, 0.65-0.95]), but above this cut point, higher levels conferred greater risk (hazard ratio=1.19 [95% confidence interval, 1.12-1.27]). Further adjustment for diabetes mellitus or insulin resistance, protection against which has been proposed to mediate the beneficial relationships of adiponectin with outcome, attenuated the association in the lower range. There was no significant association in group 2, but in group 3, total adiponectin showed a direct adjusted association. Additional adjustment for putative metabolic/inflammatory intermediates suggested a direct association for group 2, and magnified the one for group 3 (hazard ratio=1.31 [1.15-1.50]). Results were similar for high-molecular-weight adiponectin and for cardiovascular mortality.

CONCLUSIONS

Adiponectin exhibits distinct associations with mortality in elders, which shift from U-shaped to flat to direct with greater baseline cardiovascular dysfunction but become more consistently adverse after accounting for metabolic/inflammatory factors presumed to be favorably regulated by the adipokine. These findings advance understanding of the adiponectin paradox as it relates to older adults.

Adiposity, adipokines, and risk of incident stroke in older men

BACKGROUND AND PURPOSE

The association between adiposity and adipocytes and risk of stroke in older adults is uncertain. We have examined the association between adiposity measures and adipocytes (adiponectin and leptin) with incident stroke events in older men.

METHODS

Prospective study of 3411 men aged 60 to 79 years with no previous diagnosis of myocardial infarction, heart failure, or stroke followed-up for an average of 9 years, during which there were 192 incident major stroke events.

RESULTS

In age-adjusted analyses, body mass index and waist circumference were not significantly associated with risk of stroke in older men, although obese men (body mass index >30 kg/m(2)) showed the lowest risk of stroke. Despite the strong positive correlation between leptin and body mass index and waist circumference, risk of stroke was significantly increased in those in the top quartile of the leptin distribution. The increased risk remained after adjustment for potential confounders, including systolic blood pressure (adjusted hazard ratios top quartile versus bottom quartile: 2.03; confidence interval, 1.27-3.27]). Further adjustment for markers of inflammation (c-reactive protein), endothelial dysfunction (von Willebrand factor), fibrinolytic activity (d-dimer), and γ-glutamyl transferase attenuated the increased risk, but risk remained significantly increased (adjusted hazard ratios, 1.73; confidence interval, 1.06-2.83]). By contrast, no association was seen between adiponectin and risk of stroke.

CONCLUSIONS

Conventional adiposity measures were not associated with increased stroke risk in older men. However, leptin (a good marker of percent fat mass), but not adiponectin, predicted stroke, suggesting a link between fat mass and stroke risk.

Reference intervals for common carotid intima-media thickness measured with echotracking: relation with risk factors

AIMS

Common carotid artery intima-media thickness (CCIMT) is widely used as a surrogate marker of atherosclerosis, given its predictive association with cardiovascular disease (CVD). The interpretation of CCIMT values has been hampered by the absence of reference values, however. We therefore aimed to establish reference intervals of CCIMT, obtained using the probably most accurate method at present (i.e. echotracking), to help interpretation of these measures.

METHODS AND RESULTS

We combined CCIMT data obtained by echotracking on 24 871 individuals (53% men; age range 15-101 years) from 24 research centres worldwide. Individuals without CVD, cardiovascular risk factors (CV-RFs), and BP-, lipid-, and/or glucose-lowering medication constituted a healthy sub-population (n = 4234) used to establish sex-specific equations for percentiles of CCIMT across age. With these equations, we generated CCIMT Z-scores in different reference sub-populations, thereby allowing for a standardized comparison between observed and predicted ('normal') values from individuals of the same age and sex. In the sub-population without CVD and treatment (n = 14 609), and in men and women, respectively, CCIMT Z-scores were independently associated with systolic blood pressure [standardized βs 0.19 (95% CI: 0.16-0.22) and 0.18 (0.15-0.21)], smoking [0.25 (0.19-0.31) and 0.11 (0.04-0.18)], diabetes [0.19 (0.05-0.33) and 0.19 (0.02-0.36)], total-to-HDL cholesterol ratio [0.07 (0.04-0.10) and 0.05 (0.02-0.09)], and body mass index [0.14 (0.12-0.17) and 0.07 (0.04-0.10)].

CONCLUSION

We estimated age- and sex-specific percentiles of CCIMT in a healthy population and assessed the association of CV-RFs with CCIMT Z-scores, which enables comparison of IMT values for (patient) groups with different cardiovascular risk profiles, helping interpretation of such measures obtained both in research and clinical settings.

Abdominal obesity vs general obesity for identifying arterial stiffness, subclinical atherosclerosis and wave reflection in healthy, diabetics and hypertensive

Background

Our aim was to analyze the relationship between abdominal obesity and general obesity, with subclinical atherosclerosis, arterial stiffness and wave reflection in healthy, diabetics and hypertensive subjects.

Methods

A cross-sectional descriptive study was made of 305 individuals (diabetics 32.8%, hypertensive subjects 37.0% and healthy individuals 30.2%). Measurements: Body mass index (BMI), waist circumference (WC), body fat percentage (BFP) and waist/height ratio (WHtR). Arterial stiffness was assessed according to pulse wave velocity (PWV), intima-media thickness of the common carotid artery (C-IMT), augmentation index (central and peripheral), ankle-brachial index (ABI), and central and peripheral pulse pressure.

Results

WC and WHtR showed a positive correlation to PWV and C-IMT in the studied groups. After adjusting for age, gender, high sensitivity c-reactive protein, serum glucose and the presence of diabetes, hypertension, smoking, dyslipidemia, antidiabetic drugs, lipid-lowering drugs, and atherosclerotic plaques, it was seen that for every 0.1 point increase in WHtR, and for every cm increase in WC, the PWV increased 0.041 and 0.029 m/sec, and C-IMT increased 0.001 mm and 0.001 mm, respectively.

Conclusions

The measures of abdominal obesity (WHtR and WC) correlates better than BMI and BFP with arterial stiffness evaluated by PWV, and with subclinical atherosclerosis evaluated by C-IMT, independently of the presence of diabetes or hypertension.

Trial Registration

Clinical Trials.gov Identifier: NCT01325064

Total and high-molecular-weight adiponectin and risk of incident diabetes in older people

OBJECTIVE

To delineate the associations of total adiponectin, high-molecular-weight (HMW) adiponectin, and the HMW-to-total adiponectin ratio with diabetes in older adults.

RESEARCH DESIGN AND METHODS

Total and HMW adiponectin were measured in a population-based study of older adults. The relations of total adiponectin, HMW adiponectin, and their ratio with incident diabetes (n = 309) were assessed in 3,802 individuals.

RESULTS

Total and HMW adiponectin were highly correlated (r = 0.94). Analysis using cubic splines revealed that the associations between total and HMW adiponectin and new-onset diabetes were not linear. Specifically, after adjustment for confounders, there were similar inverse relationships for total (hazard ratio per SD 0.49 [95% CI 0.39-0.63]) and HMW adiponectin (0.42 [0.32-0.56]) with diabetes up to values of 20 and 10 mg/L, respectively, above which the associations plateaued. These associations persisted after adjustment for potential mediators (blood pressure, lipids, C-reactive protein, and homeostasis model assessment of insulin resistance [HOMA-IR]). There was, however, evidence of interaction by HOMA-IR in the lower range of adiponectin, with stronger inverse associations among insulin-sensitive than insulin-resistant participants. HMW-to-total adiponectin ratio showed a linear adjusted association with outcome, but this was abolished by inclusion of mediating variables.

CONCLUSIONS

In this older cohort, increasing concentrations of total and HMW adiponectin were associated with comparably lower risks of diabetes, but these associations leveled off with further increases above concentrations of 20 and 10 mg/L, respectively. The more pronounced risk decreases at the lower range among participants without insulin resistance support a role for adiponectin that is independent of baseline hyperinsulinemia, but this will require further investigation.

[Identification and quantification of fat compartments with CT and MRI and their importance]

In addition to being overweight, as defined by the BMI, the distribution, composition and biological activity of adipose tissue are key elements in the cardiovascular risk stratification of patients. Several non-invasive techniques have been developed to quantify local fat depots, whereby computed tomography (CT) and magnetic resonance imaging (MRI) are the most important. In general adipose tissue is subdivided into subcutaneous and visceral compartments and although both are associated with cardiovascular risk factors and disease, visceral fat has on average a stronger association and a clearly higher biological activity independent of traditional risk factors. This maybe explained by the higher endocrine activity and secretion of pro-inflammatory cytokines by visceral fat. Especially pericardial adipose tissue, a local visceral fat depot surrounding the coronary arteries, is associated with the presence, extent and severity of coronary artery disease. However, several other local fat depots have been identified and associations with various diseases have been established. This article gives an overview over the current methods for the identification and quantification of local fat depots and summarizes the hypothesized and known associations. Furthermore, it gives an overview of the potential significance of individual local fat depots for cardiovascular risk stratification.

Adverse Associations between Visceral Adiposity, Brain Structure, and Cognitive Performance in Healthy Elderly

The link between central adiposity and cognition has been established by indirect measures such as body mass index (BMI) or waist–hip ratio. Magnetic resonance imaging (MRI) quantification of central abdominal fat has been linked to elevated risk of cardiovascular and cerebro-vascular disease. However it is not known how quantification of visceral fat correlates with cognitive performance and measures of brain structure. We filled this gap by characterizing the relationships between MRI measures of abdominal adiposity, brain morphometry, and cognition, in healthy elderly. Methods: A total of 184 healthy community dwelling elderly subjects without cognitive impairment participated in this study. Anthropometric and biochemical markers of cardiovascular risk, neuropsychological measurements as well as MRI of the brain and abdomen fat were obtained. Abdominal images were segmented into subcutaneous adipose tissue and visceral adipose tissue (VAT) adipose tissue compartments. Brain MRI measures were analyzed quantitatively to determine total brain volume, hippocampal volume, ventricular volume, and cortical thickness. Results: VAT showed negative association with verbal memory (r = 0.21, p = 0.005) and attention (r = 0.18, p = 0.01). Higher VAT was associated with lower hippocampal volume (F = 5.39, p = 0.02) and larger ventricular volume (F = 6.07, p = 0.02). The participants in the upper quartile of VAT had the lowest hippocampal volume even after adjusting for age, gender, hypertension, and BMI (b = −0.28, p = 0.005). There was a significant age by VAT interaction for cortical thickness in the left prefrontal region. Conclusion: In healthy older adults, elevated VAT is associated with negative effects on cognition, and brain morphometry.

Associations of IGF1 and IGFBPs 1 and 3 with all-cause and cardiovascular mortality in older men: the Health In Men Study

OBJECTIVE

Circulating IGF1 declines with age while ill-health increases. Controversy remains whether differences in the levels of IGF1 and its binding proteins 1 and 3 (IGFBP1 and IGFBP3) determine health outcomes during ageing. We examined associations of IGF1, IGFBP1 and IGFBP3 with all-cause and cardiovascular mortality in older men.

DESIGN

We conducted a prospective cohort study of community-dwelling men aged ≥70 years.

METHODS

Plasma collected at baseline (2001-2004) was assayed for total IGF1, IGFBP1 and IGFBP3. Incidence and causes of death from time of recruitment to 31 December 2008 were ascertained using the Western Australian Data Linkage System. Cox regression analyses were performed, adjusting for conventional cardiovascular risk factors.

RESULTS

Among 3983 men followed for 5.2 years (median), 694 deaths occurred, 243 from cardiovascular disease (CVD). There was no difference in survival according to quintiles of IGF1. Increased IGFBP1 predicted increased all-cause mortality (highest versus lowest quintile: adjusted hazard ratio (HR)=1.98, 95% confidence interval (CI)=1.52-2.57, P<0.001 for trend) and increased cardiovascular mortality (HR=3.42 (2.03-5.77), P<0.001 for trend). Decreased IGFBP3 predicted increased all-cause mortality (lowest versus highest quintile: HR=1.57, 95% CI=1.23-2.01, P=0.007 for trend). Associations of IGFBP1 and IGFBP3 with all-cause mortality were not attenuated by adjustment for IGF1 levels.

CONCLUSIONS

In older men, higher IGFBP1 and lower IGFBP3 levels predict overall and CVD-related mortality, while IGF1 levels are not associated with mortality. Further studies are needed to clarify the underlying mechanisms by which IGFBP1 and IGFBP3 levels are associated with mortality risk, and whether this occurs independently of IGF1.

Separate and combined associations of body-mass index and abdominal adiposity with cardiovascular disease: collaborative analysis of 58 prospective studies

BACKGROUND

Guidelines differ about the value of assessment of adiposity measures for cardiovascular disease risk prediction when information is available for other risk factors. We studied the separate and combined associations of body-mass index (BMI), waist circumference, and waist-to-hip ratio with risk of first-onset cardiovascular disease.

METHODS

We used individual records from 58 cohorts to calculate hazard ratios (HRs) per 1 SD higher baseline values (4.56 kg/m(2) higher BMI, 12.6 cm higher waist circumference, and 0.083 higher waist-to-hip ratio) and measures of risk discrimination and reclassification. Serial adiposity assessments were used to calculate regression dilution ratios.

RESULTS

Individual records were available for 221,934 people in 17 countries (14,297 incident cardiovascular disease outcomes; 1.87 million person-years at risk). Serial adiposity assessments were made in up to 63,821 people (mean interval 5.7 years [SD 3.9]). In people with BMI of 20 kg/m(2) or higher, HRs for cardiovascular disease were 1.23 (95% CI 1.17-1.29) with BMI, 1.27 (1.20-1.33) with waist circumference, and 1.25 (1.19-1.31) with waist-to-hip ratio, after adjustment for age, sex, and smoking status. After further adjustment for baseline systolic blood pressure, history of diabetes, and total and HDL cholesterol, corresponding HRs were 1.07 (1.03-1.11) with BMI, 1.10 (1.05-1.14) with waist circumference, and 1.12 (1.08-1.15) with waist-to-hip ratio. Addition of information on BMI, waist circumference, or waist-to-hip ratio to a cardiovascular disease risk prediction model containing conventional risk factors did not importantly improve risk discrimination (C-index changes of -0.0001, -0.0001, and 0.0008, respectively), nor classification of participants to categories of predicted 10-year risk (net reclassification improvement -0.19%, -0.05%, and -0.05%, respectively). Findings were similar when adiposity measures were considered in combination. Reproducibility was greater for BMI (regression dilution ratio 0.95, 95% CI 0.93-0.97) than for waist circumference (0.86, 0.83-0.89) or waist-to-hip ratio (0.63, 0.57-0.70).

INTERPRETATION

BMI, waist circumference, and waist-to-hip ratio, whether assessed singly or in combination, do not importantly improve cardiovascular disease risk prediction in people in developed countries when additional information is available for systolic blood pressure, history of diabetes, and lipids.

FUNDING

British Heart Foundation and UK Medical Research Council.